These are vertical lines that develop on the skin part of the lip. They commonly but not necessarily come from smoking. Best results are achieved for patients with a few large but not highly etched-in wrinkles. For this procedure Botox should be given in minimal doses (0.5-1 U per wrinkle) to minimize weakness in this area, as lips have an essential role in facial functioning. Combination treatment with Juvederm may be required for optimal results in these patients. Even in appropriate doses, Botox injections in this area may prevent patients from being able to drink through a straw or whistle.